In the 20th century, Karl Rahner (1904-1984) was for Roman Catholic theology what Karl Barth was for Protestant theology, and some have even placed him in line with the greatest theologians, such as Aquinas and Schleiermacher (see Roger Olson, The Journey of Modern Theology, 550). His work continues to be discussed throughout the Catholic world, beyond the context of Europe and North America. For example, during my visit to El Salvador in early 2015, a number of Catholic activists who I spoke to referenced Rahner (alongside liberation theologians like Sobrino and Gutierrez, of course) as crucial to their own Christian thinking. Indeed, both Catholics and Protestants are often impressed by Rahner’s efforts to strike a balance between traditional Catholic dogma and modernism (i.e., post-Enlightenment philosophies, biblical criticism, history of religions, the natural sciences, etc.). Like Paul Tillich, Rahner was therefore a mediating theologian who recognized the “pluralism” and “fragmentation” of theology in modernity, while nevertheless arguing for a robust conception of Christian existence (FCF, 7). As such, Rahner hoped to give “an intellectually honest justification of Christian faith” (FCF, xii), and claimed that theology succeeds only when it makes “contact with the total secular self-understanding which man has in a particular epoch” (FCF, 7-8). As these quotes indicate, Rahner and Tillich share strikingly similar theological positions. This is due in part to their common philosophical sources, namely the works of Martin Heidegger and German idealists, which infuse their theologies with certain existentialist and mystical sensibilities (FCF, 24).
Perhaps Rahner’s most well known position is that persons of other religious traditions can be considered “anonymous Christians”, and thus ultimately included within salvation through Christ. He is also frequently quoted for his embrace of Christian mysticism: “In the days ahead, you will either be a mystic (one who has experienced God for real) or nothing at all.” Rahner’s inclusivism and mysticism point to one of the defining characteristics of his theology: a core concern to overcome any sharp dualism between God and creation. Rahner thus offered an intriguing doctrine of God in Foundations of Christian Faith that aimed to balance revelation and reason, transcendence and immanence. This did not result in a loss of God’s radical otherness. On the contrary, although Rahner viewed God as the “innermost center of our existence” (FCF, 12), he also spoke of God as absolute “mystery” and “abyss” (FCF, 2-3, 42).
Like most Catholic theologians, Rahner affirmed a certain kind of natural theology: that God can be partially known outside of special revelation: “theology itself implies a philosophical anthropology which enables [the] message of grace to be accepted” (25). For Rahner, there is indeed an essential “point of contact” between God and the creature. He thus disagreed with Barth’s “too narrowly Christological approach,” and advocated a transcendental theological method that begins with an analysis of human existence. This existential analysis ultimately demonstrated for Rahner that all humans have an “unthematic” knowledge of divinity as the absolute mystery of existence (FCF, 13, 18, 21). This is not an “objectifying” knowledge of God, and it is insufficient without the explicitly “thematic knowledge” of God derived from religious activity (FCF, 53). But thematic knowledge (i.e., revelation) requires an unthematic ground in order to be received, Rahner believed. He even claimed that this existential argument for the existence of God is “the one proof” that is legitimate, while all other “reflexive” arguments for God (whether cosmological, moral, etc.) only serve as necessary pointers to or clarifications of God as existential ground (71).
Thus Rahner paradoxically concluded that “holy mystery” is that which is “most self-evident,” because it is the presupposed ground for human knowledge of anything. Without this mysterious ground that gives everything existence, human comprehension of the world would be impossible: “Man is a transcendent being insofar as all of his knowledge and all of his conscious activity is grounded in a pre-apprehension of ‘being’ as such...” (33). But with Heidegger, Rahner maintained that this pre-thematic awareness of the ground of existence is always indirect and “never captured by metaphysical reflection.” It can be approached “if at all, in mystical experience and perhaps in the experience of final loneliness in the face of death.” (35). Thus in God’s radical immanence as the ground of existence, God remains simultaneously transcendent to the creature (58).
But why must this ground be named “God”? Part of Rahner’s surprisingly simple answer is that “God” is that enduring historical name for the uniting ground of reality, which humans necessarily wonder about as finite beings. In other words, “God” provides the most reasonable answer to the ontological question: “why is there something rather than nothing?” While Rahner thus identified God with Being-itself – as “holy mystery” – he admitted that one might call the ground of being “a thousand other names,” apart from thematic knowledge of God in Christ (60). This point raised some questions for me at this crucial moment in Rahner’s argument: why is it necessary to view the world as grounded in an original “unity” of Being at all, as Rahner claimed? Why not a differential abyss (Derrida), an unconscious ocean of virtual singularities (Deleuze), or a process of becoming without origin or final goal (Whitehead)? Why must existence be grounded in an original cosmic purpose, as Rahner claimed, rather than ungrounded in sheer chance? Can Rahner truly justify his Christian appropriation of Heidegger’s nontheistic ontology while yet transforming it into a kind of panentheism (this is always a problem for Heidggerian theologians – e.g., John Macquarrie)? I simply do not see how any existential analysis of humans “proves” that either God or unity grounds all of reality.
Although Rahner claimed to have avoided ontotheology by denying explicit conceptual knowledge of Being-itself (much like Tillich), he nevertheless attributed to it – without any apparent justification – a quasi-teleological function of unity (FCF, 64). How is this not thematic/conceptual knowledge of Being/God? This logocentric assumption that the world’s finite multiplicities are ultimately grounded in and derived from an original unity remains highly contestable, to say the least. I actually found this same rationalistic assumption in Wolfhart Pannenberg’s Systematic Theology I, in which he appropriates Rahner’s notion of an unthematic knowledge of God as uniting ground of being. Perhaps this is the enduring legacy of Hegel’s rationalism in so much European theology: that unity must be primordial, while difference is derivative. But in my view, this rationalistic-monotheistic assumption can only be defended (if at all) on the “grounds” of special revelation – and thus on a groundless risk of faith. Even so, I am not convinced that theology necessarily collapses into either total fideism or chaotic relativism when it departs from Rahner by more thoroughly resisting ontotheological temptations.